Micro Adjustment

Spoony · 3 Jul 2011

I dont really understand it.

Can it be done on any camera? Does everybody check or is it only used if images are soft?

How is it done, if someone can explain or point me in the right direction that would be fab.

Not worried about my images as thats user error, just wondering!

HoppyUK · 3 Jul 2011

It was only a couple of years ago that no cameras had AF microadjust, but somehow we managed.

Only top-end cameras have it now, and your D5000 is not amongst them. Could be a blessing in disguise - it seems to create more (imaginary) problems that it solves.

rssmrry · 3 Jul 2011

Gotta agree with Richard. Seems many people buy a lens then take photos of a chart and remark how bad it is or get some batteries out and do that same thing.

Way I see it (and I don't have a camera that can MA) you should only do it if you're going to get a noticeable improvement.

hollis_f · 3 Jul 2011

It is quite handy - with prime lenses. Zooms tend to want different values at different focal lengths. But I wouldn't go all weepy-waily if a camera didn't have it.

Spoony · 3 Jul 2011

Well I wonder no more, cheers for the responses.

As a noob you hear or read about new things all the time,

I was interested if I should be checking my lenses, but I would not know where to start.

Cheers

gunnar · 3 Jul 2011

Spoony said:
I was interested if I should be checking my lenses, but I would not know where to start.

Don't check unless you see focus issues on your real life shots. Pixel peeping and lens testing is a road to hell

Johnd2000 · 4 Jul 2011

I have to disagree with the consensus here that MA is unnecessary. I have two bodies and getting on for a dozen lenses. On my crop sensor body (no MA) I have some lenses that are great, but some I just can't use because they are too soft. On my FF body, all my lenses are (i believe) as sharp as they are ever going to get, because I spent maybe 4-5 hours over a weekend fine tuning using MA. Only two of my lenses didn't need some adjustment on the FF body, which kind of horrified me until I realised that the range of adjustment (both negative and positive) suggests that the body itself isn't particularly out in any direction.

My experience, and the frequent "should I return this lens?" threads I read here and on other forums, suggests to me that MA is a really useful feature. In fact, I don't think I'd buy a camera without it now.

HoppyUK · 4 Jul 2011

Johnd2000 said:
I have to disagree with the consensus here that MA is unnecessary. I have two bodies and getting on for a dozen lenses. On my crop sensor body (no MA) I have some lenses that are great, but some I just can't use because they are too soft. On my FF body, all my lenses are (i believe) as sharp as they are ever going to get, because I spent maybe 4-5 hours over a weekend fine tuning using MA. Only two of my lenses didn't need some adjustment on the FF body, which kind of horrified me until I realised that the range of adjustment (both negative and positive) suggests that the body itself isn't particularly out in any direction.

My experience, and the frequent "should I return this lens?" threads I read here and on other forums, suggests to me that MA is a really useful feature. In fact, I don't think I'd buy a camera without it now.

Can't really disagree with that John, I use AF Micro adjust myself, but only...

If you are using low f/number lenses in critical situations
If your technique is good enough for AF microadjust to be a significant factor
If you have a known, real problem, observed in actual picture taking that is not simply user-error (it mostly is)
If you use an appropriate test, as opposed to the mass of frankly wrong and misleading advice out there
And if you know exactly what you're doing

Unless those things apply, many people just make things worse, or create problems where none exists. The honest answer to most of the "should I return this lens?" threads is NO - learn to use it properly. But not all LOL

cyclamens · 4 Jul 2011

Having come from a background of manual focus lenses I have become intrigued by this 'Micro Adjustment' thing which appears regularly in the forum.

If the shot is 'soft' when you've manually focussed - easy - you're wrong.
I thought, incorrectly it seems, that auto focus was the be all and end all. I regularly get 'soft' shots with my 5DMkII and the 24/105L lens - but then I also get really sharp ones. I had never heard the term 'front', or, 'rear focussing' until I started reading some of the equipment reviews or reading posts on here.

It's also amazing the difference when an image has been 'sharpened' in processing software.

I have, indeed, wondered if I should get my lenses checked - or maybe my technique :help:

Seems to me there's a business opportunity here for someone

artyman · 4 Jul 2011

Micro Adjustment doesn't affect the inherrent softness or sharpness of a lens, it just moves the bit in focus backwards or forwards by a small amount to correct autofocus if it getting it slightly wrong. For instance if you focus on a birds eye, but it is slightly fuzzy but the tail is sharper, that would mean the lens is backfocusing. All this assumes you got the focusing part of the shot correct in the first place and hadn't introduced user error.

HoppyUK · 4 Jul 2011

artyman said:
Micro Adjustment doesn't affect the inherrent softness or sharpness of a lens, it just moves the bit in focus backwards or forwards by a small amount to correct autofocus if it getting it slightly wrong. For instance if you focus on a birds eye, but it is slightly fuzzy but the tail is sharper, that would mean the lens is backfocusing. All this assumes you got the focusing part of the shot correct in the first place and hadn't introduced user error.

And further, if the AF is out of adjustment, it will always be out, by the same amount, and in the same direction.

If the focus is inconsistent, as Barry says, then it's got to be user error.

Johnd2000 · 4 Jul 2011

HoppyUK said:
And further, if the AF is out of adjustment, it will always be out, by the same amount, and in the same direction.

If the focus is inconsistent, as Barry says, then it's got to be user error.

I agree but DOF will mask minor calibration issues at smaller apertures. I only ever test lenses wide-open for that reason.

It's a fair point that technique will have a far greater effect on sharpness than precisely how close to tolerance the lens and body (combined) are. IS/SS seems to have convinced us all that we should be able to shoot at 200mm (with a big heavy metal lens) at 1/25 hand-held.